Most achingly-beautiful music

Four Last Songs - Strauss (Elisabeth Schwarzkopf's recording)
Dvorak Cello Concerto (Rostropovich)
Sibelius Violin Concerto
Beethoven 6th symphony
Mozart Piano Concerti nos. 20, 21, 23, 27

This famous Korean Kpop song :

http://www.youtube.com/watch?v=BqtRO_Pmyxg&feature=fvsr

Joni Mitchell: "A case of you".

Jeff Buckley: "Hallelujah"

I'd like to add "Lush Life" by Ella Fitzgerald accompanied by Joe Pass on Pablo, 1974. Her real-life unrequited love is palpable in this rendition and Pass's sensitive backing is perfect. Great suggestions from all.

Sheila Jordan paired with Steve Kuhn on the early ECM releases.

"Hope", written by Joey Calderazzo, as performed by the Branford Marsalis Quartet on "Braggtown"